A data terminal, also known as a Wireless Internet Terminal, may be connected to a wireless wide area network. The data terminal functions as a modem but is small in size and portable. The data terminal is mainly applied to user equipment such as notebook computers or desktop computers, and is connected with user equipment via a USB interface thereof
In the prior art, the USB interface of the data terminal is usually a direct plug-in type USB interface. In application, such a direct plug-in type USB interface needs a user to remove a USB cap covered on the USB interface, so that the USB interface is exposed and plugged into the user equipment.
However, in the prior art, after the direct plug-in type USB interface is used for a period of time, the fitting between the USB cap and the USB interface is likely to become loose, and as a result, the USB cap may be missing.